Check out my example here, the red square represents any visible content that might be present in the scene.ĭraggable rotating plane: I needed to replicate the ability to click and drag to change the viewing angle. After reading the following GitHub thread I realised I had to update the Three.js camera’s field of view (FOV) upon window resize, and after some mathematical trial and error I managed to get it working. The “Responsive Design” article on Three.js Fundamentals got me most of the way there, but when viewed in a mobile-esque portrait aspect the sides of the demo spinning cube would be clipped, whereas I wanted the content to resize itself to always fit within that central square area so it would always be visible. This is so that the entire visualisation would be visible regardless of window aspect. I needed the canvas to not only resize itself to fit the size of the browser window, but I also wanted the contents to always occupy a square area located in the centre of the canvas, regardless of window aspect ratio. Resizable canvas: by default, Three.js outputs to a 300x150px canvas element that does not resize. I followed their Hello World tutorial and got a cube rotating onscreen pretty quickly. I couldn’t have completed this project without it, it really was incredibly useful. While researching this I discovered an amazing learning resource in the form of the tutorials at Three.js Fundamentals. Hello World: the objective was to get something simple onscreen. Once I’d developed them all, I would then put the various components together and develop the final app. Rather than diving straight into rebuilding the application in one go, I decided to break it down into various chunks of essential functionality required to complete the final product. Three.js/WebGL: Interactive Perlin Noise Landscape Visualisation by Sebastian Lenton ( CodePen. TL DR: view the new Three.js version of my app in the embed below, or right here on Codepen. There are other options of course, but I chose Three.js as there’s a wealth of demos and documentation for it out there, plus it seems like the one I see in the wild the most. However, WebGL can be somewhat impenetrable to newcomers, requiring an intimate knowledge of graphics programming and mathematics, so many developers add a library or framework on top to handle the heavy lifting.Īnd that’s where Three.js steps in, providing a relatively simple API for developing WebGL apps. In the right hands, the visual output can be more akin to a modern PC or console video game than the more simplistic animated graphics you might usually see around the web. So, what is WebGL, and what’s Three.js? WebGL is a hardware-accelerated API for drawing graphics in a web browser, enabling 2D and 3D visuals to be drawn with a far higher level of performance than what you might get when using the DOM or a HTML5 canvas. Browsers aren’t well equipped when it comes to transforming thousands of divs in 3D, so in pursuit of a better frame rate I decided to use this as an excuse to finally dip into WebGL, by rewriting the app using a WebGL-based renderer. It turned out pretty well, but I found that the frame rate absolutely tanked when adding divs to increase the visualisation’s resolution. The 3D graphics are drawn in the browser DOM, using thousands of divs transformed via CSS. I've drawn a 2d grid with a part on it (this is part of some CNC software I'm working on) but as you can see the grid lines that intersect the bottom of the camera are disappearing as i zoom into them.Ī few screen shots of the problem (zooming into the object by incrementing while ago I developed a little demo app that generates an interactive 3D visualisation – a primitive landscape of sorts – from a number sequence generated by a Perlin Noise algorithm (don’t worry if that means nothing to you!). The lines in the screenshots bellow use THREE.ColorStrokeMaterial and have overdraw set to true (btw. Perhaps this is a problem with my near clip (0.000001) or far clip (1000000) being set poorly (those values were based on no real 3d programming experience) but it could also be a bug so I'm posting it here in hopes of some help with the issue. When I zoom into a object (which I do by incrementing the z vector of the camera position in three.js) I find that once I get to close lines start disappearing while they should still be in the viewing area.
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